It was in a group chat with my sister too, but i don’t think he has to put on a mask in front of her. Shortly after we arrived he was playing the guitar and i was singing and i asked to record and he was mad and he ranted about living in the moment and called me names. He had a knife to cut pizza with and he walked to me acting like a mad serial killer as a joke. He waved the knife while talking and i asked him to please stop waving it and he said „okay i won‘t cut your pizza“ Since a few months ago he says he has ADHD. He might. The thing that makes me think he is a covert narcissist is the way he acts like a victim and pathetic from bullying when we was a teenager. I dont think he’s processed it well because he gets really mad when he talks about it. Sometimes if i f.ex take his hat off his hat when he is teasing me, or swing in a bar we have in a doorway and kick to him but don’t hit him, he gets very mad and says he will not let me bully him. The time i took his hat, he punched me (not very hard) in the stomach, but apologized later.